The present invention relates to absorbent garments for absorbing bodily fluids (such as urine, blood or faeces) as defined in the preamble of claim 1. In particular, but not exclusively, the invention relates to absorbent garments of the disposable type. Absorbent garments of the present invention may be of several types, for example diapers (nappies) for adult or infant use, such as incontinence diapers, reclosable absorbent pants (e.g. training pants for infant use), or the like. Typically the garments of this invention will comprise a top sheet, a back sheet and an absorbent body therebetween.
Even more particularly the present invention relates to absorbent garments having cooperating releasable (sometimes known as xe2x80x9creclosablexe2x80x9d) attachment means.
An example of an absorbent garment of the type according to the preamble of claim 1 is known from WO-A-90/07313 for example. The cooperating attachment means disclosed therein are disposed on the front and rear waist parts. On the front waist part, the attachment means comprises two attachment portions consisting of strips of receiving material, which strips are spaced apart so as to lie on either side of an elasticated section of the diaper waistband itself. Such an arrangement means that the elasticated portion of the waistband has to be made to extend from the waist region down to a location between the attachment means. Additionally, attachment of the cooperating hook members to the receiving material is dependent on the elastic arrangement of the waistband itself so that two functions of attachment and waistband extension are dependent on one another which does not allow for optimal fitting of the diaper. Furthermore, the elastic material in the waistband cannot extend laterally beyond the inner margins of the receiving material since otherwise attachment of the receiving material on to a gathered section would result in unsatisfactory results.
A further known prior art arrangement is shown in EP-A-0 491 347. This document discloses a disposable diaper in which the front attachment means on the front waist portion of the article is constituted by a strip of loop material. In one embodiment, said strip is affixed to the impermeable back sheet by means of spaced beads of adhesive, thus allowing tension forces applied thereto (by the attachment of hook tabs) to distort and buckle portions of the loop strip. In this way the peel, shear and latching forces can be altered. In a further embodiment, the hook tab members can be made of elastomeric material.
In a further prior art document WO-A-95/25496, also aimed at altering the peel strength between hook and loop attachment materials, a landing member of loop material having slits therein may be attached around its whole periphery to the front waist portion of an absorbent article. In one embodiment, it is disclosed that the integrity and appearance of the landing member may be better preserved when under tension if an elastomeric adhesive is used to secure the landing member inside the said peripheral attachment line. In this way, when tension forces are released from said landing member, the landing member will return to its undeformed condition.
The aforementioned systems thus relate to achieving a change in the peel strength between the hook and loop members.
Whilst EP-A-0 491 347 provides elastication of the hook tabs to produce the desired effect, this has the disadvantage that the elastication forces are constrained to be at the two side portions of the article. Additionally a wrinkling or lifting of the front attachment means may occur.
The object of the present invention is to provide an absorbent garment having attachment means (not restricted to hook and loop types) which provides a better fit around a wearer of said garment and thus provides a high degree of comfort to the wearer.
In one embodiment, the an absorbent garment for use in absorbing bodily fluids has a front waist portion with front attachment means and a rear waist portion with rear attachment means, wherein the front and rear attachment means provide cooperating surfaces allowing attachment of said front and rear attachment means together, wherein the garment has a longitudinal axis extending substantially between mid-portions of the front and rear waist portions and wherein the front attachment means extends transversely with respect to said longitudinal axis, wherein the front attachment means comprises two separate attachment portions and at least one elastic section comprising elastic material, the attachment portions each being attached to said at least one elastic section such that movement of the attachment portions away from each other causes stretching of at least one elastic section.
Preferred features of the invention are defined in the dependent claims.
Further features applicable to the invention will be clear from the following description.
The term xe2x80x9cmid-portionxe2x80x9d of the front and rear waist portions, as used to define the position of the longitudinal axis (Xxe2x80x94X) of the garment, is intended to refer to a position approximately mid-way between the longitudinal side edges of the absorbent garment in the region of the front and rear waist portions. Since the exact location of a mid-way portion may vary due to manufacturing tolerances or asymmetry, such term is to be regarded as defining a location in the mid-region of said waist portions.
The term xe2x80x9cwaist portionsxe2x80x9d of an absorbent garment refers to the general areas at either end of the absorbent garment which are designed such that, when fitted to a user, they will be proximate to the front and rear portions of the user""s waist. The waist portions will often be provided with elastication means. In a diaper, these front and rear waist portions will start at an outer longitudinal edge of the diaper and extend towards the middle of said diaper by a certain distance, typically between 30 mm (typical in very small diapers) up to about 120 mm in adult incontinence diapers. The two waist portions will be joined by an intermediate region, the side edges of which are typically substantially taken up by leg-opening portions which may be elasticated. A typical ratio of proportions in a diaper is such that the extent of the waist portion inwardly towards the middle of the diaper constitutes between about 20% to 40% of the whole diaper length. Expressed in other terms, the extent of the front waist portion, when a correct size diaper is fitted correctly on a wearer, can be seen as approximating to the distance from the upper edge of the diaper, when fitted, to the top of the user""s thighs.
The term xe2x80x9cfront waist portionxe2x80x9d is intended to refer to the portion of the garment which will normally be positioned at the front of the wearer when the garment is correctly fitted as intended. However, the garment can be fitted back-to-front, in which case the front waist portion will be positioned at the wearer""s lower back.
An xe2x80x9celastic materialxe2x80x9d is intended to indicate a material which has highly elastic properties. For the purposes of this invention, such elastic properties include materials having a degree of elastic extension compared to their relaxed (non-tensioned) state being typically above 25%, more preferably above 50% and most preferably above 100%. Even more preferably, elastic materials will be used which have a degree of elastic extension compared to their relaxed state in the order of up 200% to 500% or even more in some cases. Such materials include, by way of example only, natural rubber films or polyurethane rubber (P.U.R) films, or thicker elasticated sheet materials having good elastic properties. Such materials are not to be confused with materials such as non-woven materials or the like which have elastic extensions of some 4% or less.
The exact characteristics chosen for the elastic material will be adapted to the particular type and size of absorbent garment. Thus the elastic strength, memory of the elastic film used, weight, suppleness and strength will be varied in accordance with the requirements of any specific type of garment. The term xe2x80x9celastic extensionxe2x80x9d also means that the material, when stretched, will return to it original length within certain limits. Such limits are more commonly referred to as the memory of the material. Whilst the elastic material ideally has a high memory such that it will return substantially completely to its original length when a tensioning force is released, for the purposes of this invention elastic materials returning to between 100% to about 115% or more of their original length after being stretched by at least 25% are suitable for example.
Additionally it is to be understood that the absorbent garments referred to in claim 1 may include an absorbent body, or member, as an integral part thereof, or that they may be of the type where an absorbent body or absorbent member is added. The latter type may, for example, be of the type where a garment where absorbent body or element is removable, such as in the case where the same absorbent garment is to be used several times with a replaceable absorbent body.
The front and rear attachment means are defined as having cooperating surfaces. By this it is meant that each of said first and second attachment means has a surface which will engage with, preferably in a releasable manner, the respective opposed attachment means. A preferred form of this, having regard to the present invention, would be hook and loop fastening means (known per se). Hook and loop fastening means are merely an example of what are known generally in this technical field as releasably attachable fastening means and more particularly as releasably attachable mechanical fastening means. The hook and loop attachment means thus provide mechanically interengaging, or in other words mechanical cooperation, between each other. An example of such mechanical fastening means is for example sold under the trademark xe2x80x9cVelcroxe2x80x9d. Various types of releasably attachable mechanical fastening means are known in this field and are to be understood as included within the definition of attachment means providing cooperating surfaces. Thus where hook and loop elements or strips are referred to, it should be understood that this is merely an example and that adhesive cooperating means of releasable or non-releasable type may also constitute the front and rear attachment means respectively. Additionally the term xe2x80x9chook elementxe2x80x9d should not be interpreted narrowly and this term may include elements which are not precisely in the form of a hook, but may also be xe2x80x9cmushroomxe2x80x9d shaped (as is known per se).